Methods for registration of magnetic resonance images of ex vivo prostate specimens with histology

Abstract

Purpose: To evaluate two methods of scanning and tissue processing to achieve accurate magnetic resonance (MR)-histologic correlation in human prostate specimens. Materials and Methods: Two prostates had acrylic paint markers injected to define the plane of imaging and serve as internal fiducials. Each was placed on a polycarbonate plane-finder device (PFD), which was adjusted to align the imaging and cutting planes. Three prostates were aligned by use of a plane finder key (PFK), a polycarbonate plate that locks the specimen in a cylindrical carrier. Markers were injected for registration analysis. Prostates were imaged, then sectioned. Imaging software was used to create registration maps of the MR and histology images. Measurements between control points were made and compared. Results: Accurate correlation was achieved between MR and histologic images. The mean displacement (MD) between the corresponding registration points using the PFD technique ranged from 1.11-1.38 mm for each section. The MD for all sections was 1.24 mm. The MD using the PFK technique ranged from 0.79-1.01 mm for each section, and the MD across all sections for the PFK was 0.92 mm. Conclusion: We describe two methods that can achieve accurate, reproducible correlation between MR imaging and histologic sections in human prostatectomy specimens. © 2012 Wiley Periodicals, Inc.